Esterase activity
RAPD profiles
This organism is a CLSI control strain for antimicrobial susceptibility testing.
The current name of Candida krusei and Issatchenkia orientalis is Pichia kudriavzevii Boidin et al.

The strain was re-identified as Penicillium ludwigii, a close sister of P. ochro-chloron and P. janthinellum, based on the multigene sequence analysis. This change does not affect to its use as quality control strain for standard tests.